The present invention is based on a new and improved construction of an earthquake resistant high voltage device.
In its more particular aspects, the present invention specifically relates to a new and improved construction of an earthquake resistant high voltage device containing at least one connection to a high voltage line and at least one high voltage insulator connected between a high voltage side of the high voltage device and ground potential. An earthquake reistant high voltage device of this type is known, for example, from the Austrian journal: "Elektrotechnik und Maschinenbau" (E and M), volume 101, issue 7 (1984), pages 336-343. According to this publication, inadmissible stresses can occur in circuit breakers at the mounting points of the lower porcelain supports without special protective measures. To safeguard against earthquakes, it is proposed to use stronger porcelain supports or damping elements for circuit breakers. In addition, it is recommended to connect tightly strung cables to the electrical devices so that these devices can deform by about .+-.15 cm during an earthquake before the cables are tightly stretched and significant cable forces are transmitted. An abrupt pulling of the cables can result in damage in the porcelain, particularly in the case where the porcelain exhibits fine cracks.
With respect to the relevant prior art, additional reference is made to U.S. Pat. No. 3,726,986, granted Apr. 10, 1973, from which it is known to suspend an electrical device via porcelain insulators on its high voltage side and to dispose vibration dampers on the ground potential side. The disadvantageous factor in this construction is that expensive porcelain insulators are needed for the suspension and that a support frame is needed which is higher by the insulation gap which approximately corresponds to the length of these porcelain insulators.